WILLIAM G. CALLOW, J.
This is a review of an unpublished decision of the court of appeals which affirmed a judgment of conviction entered by the circuit court for Columbia county, Judge Lewis W. Charles, which found William Hartman guilty of second-degree sexual assault.
On review, William Hartman (Hartman) raises two issues. First, in a criminal case in which the defendant is charged with having sexual intercourse with a girl between the ages of twelve and sixteen, can the state enter into evidence the results of human [4]*4leukocyte antigen and red blood cell tests? Second, did the admission of expert testimony that Hartman was the father of the victim’s child deny Hartman due process and a fair trial? We conclude that two of the statistics generated by the human leukocyte antigen tests — the probability of exclusion and paternity index — are admissible in a criminal case in which the defendant is charged with sexual assault. However, we conclude that a third statistic — the probability of paternity — is inadmissible in such a case. Because the state’s introduction into evidence of Hartman’s probability of paternity based upon the human leukocyte antigen tests constituted prejudicial error, we reverse the decision of the court of appeals. Because we conclude that the admission of the probability of paternity constitutes prejudicial error and, therefore, requires a new trial, we do not reach the question of whether the admission of expert testimony that Hartman was the father deprived Hartman of due process or denied him a fair trial.
In August of 1985, defendant Hartman was charged with two counts of second-degree sexual assault. The charges were based upon allegations that Hartman had sexual intercourse with a fourteen-year-old girl, B.S., on or about April 7, 1984, and on or about April 15, 1984. Hartman interposed an alibi defense, and the case proceeded to trial in January, 1986.
At trial, B.S. testified to the following. On Saturday, April 7, 1984, B.S. went to her father’s house to pick up some money to pay for bowling. Upon arriving at the house, she knocked on the door and was let into the house by Hartman, the brother of her father’s roommate. Hartman was the only one home at the time. After searching unsuccessfully in the kitchen, [5]*5B.S. went to her father’s bedroom to look for the bowling money.
According to B.S., Hartman followed her into the bedroom and asked several times if she wanted to go to bed with him. Although B.S. refused repeatedly, Hartman eventually pushed her onto the bed and had sexual intercourse with her. Both Hartman and B.S. left the house shortly thereafter. B.S. did not tell anyone at that time what had happened.
On Sunday, April, 15, 1984, B.S. was at her father’s house with her father and brothers. After her father and brothers left to play ball, B.S. went into the bathroom to get some dirt out of her eye. While she was trying to clear the dirt from her eye, Hartman entered the bathroom, removed B.S.’s clothing, and had sexual intercourse with her on the bathroom floor. B.S. also did not immediately tell anyone of this second incident.
In October, 1984, B.S. told the police and her mother that she had been raped in a ravine by a man she did not know. About a week later, B.S. went back to the police station, recanted her story about the man in the ravine, and told the police that Hartman had raped her.
B.S. further testified that she was fourteen years of age at the time Hartman had sex with her and that she became pregnant during 1984. According to B.S. her last menstrual cycle was on or about March 20, 1984. Moreover, she did not have sexual intercourse with anyone other than Hartman between her last menstrual period and the birth of the baby.
George Gaucys (Gaucys), director of the Histocom-patibility Laboratory at the Madison Red Cross, testified concerning the results of human leukocyte antigen (HLA) and red cell tests which were done on [6]*6blood samples taken from B.S., her child, and Hartman. According to Gaucys, 98.48 percent of all falsely accused men would be excluded by the tests run in this case. Moreover, Hartman could not be excluded as the father under the tests "[bjecause [Hartman] had the necessary, or obligatory haplotype, or genes, to be the father of this child.”
Gaucys further testified that the tests indicated that Hartman had a paternity index of fifty-six. According to Gaucys, a paternity index of fifty-six "means that this man, William Hartman, is 56 times more likely to be the true father than a random man from the same population.” Gaucys also testified that there was a 98.26 percent chance that Hartman was the real father. According to Gaucys, the chance that Hartman was the father, or the probability of paternity, was based upon assuming a 50 percent chance. When asked to explain what was meant by a 50 percent chance, Gaucys stated: "Fifty percent prior chance, or prior probability. This shows that the laboratory is completely neutral. We don’t give any weight for or against this particular man in this case.” Moreover, the 50 percent prior chance did not take into account accessibility, whether Hartman lived in the same community or any factors outside of the genetic evidence. Based upon the test results, Gaucys concluded that paternity was "very likely.” In conclusion, Gaucys testified that the probability of paternity could never reach 100 percent because it was possible that another person could have the same genetic markers necessary to be the father of the child in question.
On cross-examination, Gaucys again testified that the probability of paternity could never reach 100 percent. Moreover, in response to defense counsel’s [7]*7question whether he could testify within a degree of medical certainty that Mr. Hartman is the father of this child, Gaucys stated "[w]ithin all the tests that we’ve done, and in my opinion, yes, sir.” On further cross-examination, Gaucys reiterated that the tests could not reach 100 percent, i.e., there is an element of doubt in the conclusion that Hartman is the father.
Hartman testified on his own behalf and presented a partial alibi defense. Hartman testified that he was in La Crosse on April 6, 1984, and that he returned to his parents house in the Wisconsin Dells area around noon on April 7. According to Hartman, he slept for approximately twenty minutes, at which time he was awakened by a telephone call from his brother. After arranging to go to Green Bay with his brother for a racquet ball tournament, Hartman slept a short while longer. At 2 p.m. Hartman and his brother went to Green Bay where Hartman spent the night. Hartman’s brother and a friend of Hartman offered testimony in support of Hartman’s contention that Hartman was in Green Bay on the 7th of April.
Hartman also testified that he visited friends in La Crosse from April 13 through April 16. Hartman denied being at his brother’s house on April 7 or April 15 and denied having sexual relations with B.S. at any time.
Hartman was found guilty of second-degree sexual assault for having sexual intercourse with B.S. on or about April 7,1984, and was acquitted of the charge of sexual assault stemming from the alleged incident on or about April 15, 1984. A judgment of conviction was entered, and Hartman was subsequently sentenced to an indeterminate term of not more than three years in the Wisconsin State Prison. Execution of the sentence was stayed, and Hartman was placed [8]
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WILLIAM G. CALLOW, J.
This is a review of an unpublished decision of the court of appeals which affirmed a judgment of conviction entered by the circuit court for Columbia county, Judge Lewis W. Charles, which found William Hartman guilty of second-degree sexual assault.
On review, William Hartman (Hartman) raises two issues. First, in a criminal case in which the defendant is charged with having sexual intercourse with a girl between the ages of twelve and sixteen, can the state enter into evidence the results of human [4]*4leukocyte antigen and red blood cell tests? Second, did the admission of expert testimony that Hartman was the father of the victim’s child deny Hartman due process and a fair trial? We conclude that two of the statistics generated by the human leukocyte antigen tests — the probability of exclusion and paternity index — are admissible in a criminal case in which the defendant is charged with sexual assault. However, we conclude that a third statistic — the probability of paternity — is inadmissible in such a case. Because the state’s introduction into evidence of Hartman’s probability of paternity based upon the human leukocyte antigen tests constituted prejudicial error, we reverse the decision of the court of appeals. Because we conclude that the admission of the probability of paternity constitutes prejudicial error and, therefore, requires a new trial, we do not reach the question of whether the admission of expert testimony that Hartman was the father deprived Hartman of due process or denied him a fair trial.
In August of 1985, defendant Hartman was charged with two counts of second-degree sexual assault. The charges were based upon allegations that Hartman had sexual intercourse with a fourteen-year-old girl, B.S., on or about April 7, 1984, and on or about April 15, 1984. Hartman interposed an alibi defense, and the case proceeded to trial in January, 1986.
At trial, B.S. testified to the following. On Saturday, April 7, 1984, B.S. went to her father’s house to pick up some money to pay for bowling. Upon arriving at the house, she knocked on the door and was let into the house by Hartman, the brother of her father’s roommate. Hartman was the only one home at the time. After searching unsuccessfully in the kitchen, [5]*5B.S. went to her father’s bedroom to look for the bowling money.
According to B.S., Hartman followed her into the bedroom and asked several times if she wanted to go to bed with him. Although B.S. refused repeatedly, Hartman eventually pushed her onto the bed and had sexual intercourse with her. Both Hartman and B.S. left the house shortly thereafter. B.S. did not tell anyone at that time what had happened.
On Sunday, April, 15, 1984, B.S. was at her father’s house with her father and brothers. After her father and brothers left to play ball, B.S. went into the bathroom to get some dirt out of her eye. While she was trying to clear the dirt from her eye, Hartman entered the bathroom, removed B.S.’s clothing, and had sexual intercourse with her on the bathroom floor. B.S. also did not immediately tell anyone of this second incident.
In October, 1984, B.S. told the police and her mother that she had been raped in a ravine by a man she did not know. About a week later, B.S. went back to the police station, recanted her story about the man in the ravine, and told the police that Hartman had raped her.
B.S. further testified that she was fourteen years of age at the time Hartman had sex with her and that she became pregnant during 1984. According to B.S. her last menstrual cycle was on or about March 20, 1984. Moreover, she did not have sexual intercourse with anyone other than Hartman between her last menstrual period and the birth of the baby.
George Gaucys (Gaucys), director of the Histocom-patibility Laboratory at the Madison Red Cross, testified concerning the results of human leukocyte antigen (HLA) and red cell tests which were done on [6]*6blood samples taken from B.S., her child, and Hartman. According to Gaucys, 98.48 percent of all falsely accused men would be excluded by the tests run in this case. Moreover, Hartman could not be excluded as the father under the tests "[bjecause [Hartman] had the necessary, or obligatory haplotype, or genes, to be the father of this child.”
Gaucys further testified that the tests indicated that Hartman had a paternity index of fifty-six. According to Gaucys, a paternity index of fifty-six "means that this man, William Hartman, is 56 times more likely to be the true father than a random man from the same population.” Gaucys also testified that there was a 98.26 percent chance that Hartman was the real father. According to Gaucys, the chance that Hartman was the father, or the probability of paternity, was based upon assuming a 50 percent chance. When asked to explain what was meant by a 50 percent chance, Gaucys stated: "Fifty percent prior chance, or prior probability. This shows that the laboratory is completely neutral. We don’t give any weight for or against this particular man in this case.” Moreover, the 50 percent prior chance did not take into account accessibility, whether Hartman lived in the same community or any factors outside of the genetic evidence. Based upon the test results, Gaucys concluded that paternity was "very likely.” In conclusion, Gaucys testified that the probability of paternity could never reach 100 percent because it was possible that another person could have the same genetic markers necessary to be the father of the child in question.
On cross-examination, Gaucys again testified that the probability of paternity could never reach 100 percent. Moreover, in response to defense counsel’s [7]*7question whether he could testify within a degree of medical certainty that Mr. Hartman is the father of this child, Gaucys stated "[w]ithin all the tests that we’ve done, and in my opinion, yes, sir.” On further cross-examination, Gaucys reiterated that the tests could not reach 100 percent, i.e., there is an element of doubt in the conclusion that Hartman is the father.
Hartman testified on his own behalf and presented a partial alibi defense. Hartman testified that he was in La Crosse on April 6, 1984, and that he returned to his parents house in the Wisconsin Dells area around noon on April 7. According to Hartman, he slept for approximately twenty minutes, at which time he was awakened by a telephone call from his brother. After arranging to go to Green Bay with his brother for a racquet ball tournament, Hartman slept a short while longer. At 2 p.m. Hartman and his brother went to Green Bay where Hartman spent the night. Hartman’s brother and a friend of Hartman offered testimony in support of Hartman’s contention that Hartman was in Green Bay on the 7th of April.
Hartman also testified that he visited friends in La Crosse from April 13 through April 16. Hartman denied being at his brother’s house on April 7 or April 15 and denied having sexual relations with B.S. at any time.
Hartman was found guilty of second-degree sexual assault for having sexual intercourse with B.S. on or about April 7,1984, and was acquitted of the charge of sexual assault stemming from the alleged incident on or about April 15, 1984. A judgment of conviction was entered, and Hartman was subsequently sentenced to an indeterminate term of not more than three years in the Wisconsin State Prison. Execution of the sentence was stayed, and Hartman was placed [8]*8on probation for three years, with a condition of probation to spend six months in the county jail under a work release program. Hartman appealed the judgment of conviction to the court of appeals.
In an unpublished decision, the court of appeals affirmed the judgment of conviction. First, the court of appeals rejected Hartman’s contention that Gaucy’s testimony that Hartman was the father of the child improperly bolstered B.S.’s credibility. According to the court, although opinion testimony that someone is telling the truth is inadmissible, Gaucys’ testimony was not an opinion that B.S. was telling the truth. Instead, the court concluded that the testimony merely corroborated B.S.’s claim that intercourse had occurred. According to the court, because corroborating evidence is not the same as giving an opinion that someone is telling the truth, Gaucys’ testimony that Hartman was the father of the child was admissible.
The court of appeals also rejected Hartman’s contention that the state was relieved of its burden of proof when the court instructed the jury that the state did not have to prove the exact date of the offense. According to the court, because there was no testimony concerning the exact date of the offense, the state did not have to prove the exact date of the offense. Finally, the court concluded that Hartman did not specifically object at trial to the admission of the paternity results in terms of a statistical probability. Accordingly, the court of appeals did not review that issue.
In November, 1987, we accepted Hartman’s petition for review. On review, Hartman raises only the issues of whether the circuit court erroneously admitted the HLA and red blood cell test results and whether Gaucys’ testimony that Hartman was the [9]*9father of the child improperly bolstered B.S.’s credibility. Hartman does not raise the issue of whether the jury instructions relieved the state of its duty to prove the exact date of the offense.
The state argues initially that we should not address the issue of the admissibility of the paternity statistics because Hartman did not present to the circuit court the grounds upon which he now claims the statistics were inadmissible and that this failure constitutes a waiver of his right to review. According to the state, although Hartman objected to the admission of the ■ paternity statistics, Hartman did not inform the circuit court of the objections he now raises, i.e., that admission of the test results in terms of a statistical probability deprived him of a fair trial. Hartman contends, however, that he is merely refining and expanding trial counsel’s arguments and is not raising a new issue.
We have previously held that objections to the admissibility of evidence must be made promptly and in terms which inform the circuit court of the exact grounds upon which the objection is based. State v. Wedgeworth, 100 Wis. 2d 514, 528, 302 N.W.2d 810 (1981). Moreover, an objection preserves for appeal only the specific grounds stated in the objection. Frankovis v. State, 94 Wis. 2d 141, 152, 287 N.W.2d 791 (1980). Our review of the record convinces us that the objection raised by Hartman before the circuit court was not sufficient to apprise the court of the exact grounds upon which he now challenges the admissibility of the statistical evidence.1 Accordingly, [10]*10Hartman has waived his right to object to the admissibility of the statistics derived from the HLA and red blood cell tests.
Although objections which have been waived are not reviewable as a matter of right, this court may nevertheless order a new trial if it appears from the record that the real controversy has not been fully tried or that there has been a miscarriage of justice. Sec. 751.06, Stats.2 In State v. Wyss, 124 Wis. 2d 681, [11]*11735, 370 N.W.2d 745 (1985), we recognized that there are two distinct ways in which the real controversy may not have been fully tried. First, "when the jury was erroneously not given the opportunity to hear important testimony that bore on an important issue of the case,... and [second] when the jury had before it evidence not properly admitted which so clouded a crucial issue that it may be fairly said that the real controversy was not fully tried.” Id. (citations omitted). Because we conclude that the jury in this case had evidence before it which was improperly admitted which prohibited the real controversy from being fully tried, we review Hartman’s claim of error and order a new trial.
The primary question before us is whether the circuit court erroneously admitted HLA and red blood cell test results into evidence. In this case three statistics were admitted into evidence: the probability of exclusion, the paternity index, and the probability of paternity. The first statistic — the probability of exclusion — "measures the ability of a paternity test to exclude men falsely accused of paternity.” In re Paternity of 144 Wis. 2d 638, 647, 425 N.W.2d 404 (1988). Peterson, A Few Things You Should Know About Paternity Tests (But Were Afraid to Ask), 22 [12]*12Santa Clara L. Rev. 667, 677 (1982). In other words, if the probability of exclusion was 96 percent, then 96 out of 100 falsely accused men would be excluded as the father by the tests.
The second statistic — the paternity index — is expressed as a ratio and compares the likelihood that the putative father could produce a child with the same genetic markers as the child in question with the likelihood that a random man could produce a child with the same genetic markers as the child in question. M.J.B., supra at 647. This statistic does not
describe the relative likelihood of producing the child in question, only the relative likelihood of producing a child with the same genetic markers as the child in question.
The third and final statistic — the probability of paternity — expresses the probability that the putative father is the actual father of the child in question. The probability of paternity is determined through the use of a mathematical model, Bayes’ Theorem, which describes the way new statistical information. (the paternity index) alters a previously established probability (the previously established probability that the putative father is the father of the child in question). See Ellman & Kaye, Probabilities and Proof: Can HLA and Blood Group Testing Prove Paternity?, 54 N.Y.U. L. Rev. 1131, 1147-48 (1979).
Bayes’ Theorem, however, does not define the prior probability; the prior probability of paternity must be derived independently. Typically, a 50 percent prior probability is employed to calculate the probability of paternity.3 M.J.B., supra at 648 n. 5. [13]*13Described by the state as being neutral, a 50 percent prior probability assumes a 50 percent likelihood that the defendant is the father and a 50 percent likelihood that a randomly selected man is the father. See M.J.B., at 648. In other words, the prior probability of paternity assumes that it is just as likely that the putative father is the real father as it is that he is not the real father.
With these parameters in mind, we turn to whether the paternity statistics are admissible in a criminal case in which the defendant is charged with sexual assault. Hartman argues first that paternity statistics which include the defendant as a possible father are not relevant and thus inadmissible because the statistics show only that the defendant is one of a group of possible fathers; in other words, the statistics do not conclusively prove paternity. According to Hartman, only statistics which prove nonpaternity are relevant because they are able to conclusively exclude the defendant as the father and thus prove his innocence. We disagree.
Whether evidence is relevant and thus admissible4 depends upon whether the evidence tends "to make the existence of any fact that is of consequence to the determination of the action more probable or less probable than it would be without the evidence.” Sec. 904.01, Stats.; sec. 904.02, Stats. In criminal cases in which the defendant is charged with sexual assault and a child is born consistent with the time period [14]*14indicating that the child could have been conceived as a result of the sexual assault, evidence which indicates the identity of the father is germane to a determination of whether the defendant had sexual intercourse with the victim. Moreover, because consent is not at issue when the sexual assault involves a person under the age of sixteen,5 evidence which indicates that the defendant could be the father constitutes evidence that the defendant committed the charged offense. Accordingly, the criminal cases in which the defendant is charged with sexual assault and a child is born consistent with a time period indicating that the child could have been conceived as a result of the sexual assault, evidence which tends to make it more or less probable that the defendant is the father is relevant.
We are satisfied that the probability of exclusion and the paternity index are relevant to a determination of the identity of the perpetrator of a sexual assault when the statistics include the defendant as a possible father of the child. Statistics which include the defendant as a possible father are relevant because they make the identification of the defendant as the father more probable than it would be without the statistical evidence, in that the statistics limit the number of men who could be the father.
We are not persuaded by Hartman’s argument that the statistics are not relevant because they do not conclusively determine the identity of the father. To be relevant, evidence does not have to determine a fact at issue conclusively; the evidence needs only to make the fact more probable than it would be without the evidence. Because the probability of exclusion and the [15]*15paternity index make the identification of the defendant as the father more probable, they are relevant.
Moreover, we disagree with Hartman’s contention that, because the statistics may be susceptible to misapplication, the statistics are inadmissible. We recognize the concern expressed by commentators and other courts that a jury who is told that the probability of exclusion is 98 percent may interpret this statistic to mean that it is 98 percent certain that the defendant is the father. See Commonwealth v. Beausoleil, 397 Mass. 206, 217, 490 N.E.2d 788 (1986); Peterson, supra, 22 Santa Clara L. Rev. at 678-80. However, we are satisfied that any susceptibility to misapplication can be alleviated by diligent cross-examination.6 Accordingly, we hold that the probability of exclusion and the paternity index are admissible in a criminal action in which the defendant is charged with sexual assault and the sexual assault allegedly results in the birth of a child.
Although we have concluded that the probability of exclusion and the paternity index are admissible in criminal proceedings, we are not convinced that a defendant’s probability of paternity is also admissible. Unlike the probability of exclusion and the paternity index, the probability of paternity assumes certain [16]*16facts as a condition of its calculation. As we noted earlier, the calculation of a defendant’s probability of paternity is typically based upon a 50 percent prior probability which arbitrarily assumes a 50 percent likelihood that the defendant is the father, and a 50 percent likelihood that a randomly selected man is the father. In other words, the probability of paternity is calculated based upon the assumption "that the mother and putative father have engaged in sexual intercourse at least once during the period of possible conception." M.J.B., supra at 650. Because the probabil-
ity of paternity assumes that sexual intercourse has occurred, it is improper to use this statistic to prove that sexual intercourse has occurred.
Evidence which informs the jury of the probability that the defendant is the father of a child who was alleged to have been conceived as a result of a sexual assault perpetrated by the defendant is clearly relevant to the determination of whether the defendant sexually assaulted the mother of the child. However, it is antithetical to our system of criminal justice to allow the state, through the use of statistical evidence which assumes that the defendant committed the crime, to prove that the defendant committed the crime. Because the probability of paternity assumes the fact that it is used to prove, it is inadmissible.7
[17]*17Having concluded that a defendant’s probability of paternity is inadmissible in a criminal case in which the defendant is charged with sexual assault, we hold that the circuit court erred in admitting into evidence the statistic indicating Hartman’s probability of paternity. Moreover, the crucial issue in this case is whether Hartman had sexual intercourse with B.S. Because the probability of paternity statistic appeared to provide substantial evidence that Hartman had sexual intercourse with B.S., we conclude that the erroneous admission of this evidence so clouded the determination of whether sexual intercourse occurred that the real controversy in this case was never fully tried. Accordingly, we reverse the judgment of conviction and remand the cause to the circuit court for a new trial.
Because we conclude that Hartman is entitled to a new trial, we do not address the second question before us on review — whether the admission of expert opinion testimony that Hartman was the father of B.S.’s child denied Hartman due process and a fair trial. We note, however, that when an interrogator at trial asks a witness a question and receives an answer which is responsive to the question, the interrogator is generally bound by that answer.
By the Court — The decision of the court of appeals is reversed, and the cause is remanded to the circuit court for proceedings consistent with this opinion.