Monster Energy Drink makers refuse to back down from a lawsuit claiming the energy drink was responsible for the death of a 14-year-old girl from Maryland.

According to the Huffington Post, Monster claims that no blood test was done to confirm that the Anais Fournier died of what the lawsuit says was "caffeine toxicity."

Monster's lawyer, Daniel Callahan told the AP that Fournier said her daughter had consumed energy drinks prior to her death. She believes that two Monster drinks were consumed by her daughter on the day of her death.

He also told the AP that Monster hired a team of physicians to review the medical records in the Anais Fournier case and found that she likely died of natural causes brought on by her pre-existing heart conditions. The team found no medical evidence to show caffeine was a factor.

Kevin Goldberg, a Maryland attorney for Fournier's family, said in an e-mail that the absence of a test for caffeine "doesn't tell us anything" and that the family is looking forward to a jury determining Monster's accountability.

"The fact that she went into cardiac arrest just hours after consuming the second 24-ounce Monster energy drink is evidence that she died of caffeine toxicity," he said in an email.

Goldberg said that the labeling on a Monster label is misleading. He said the company targets teenagers and young adults. Callahan said the energy drink targets 18-34 year-olds.

Fournier, according to the investigation, was a regular at Starbucks and never had an issue. Monster said in a 24-ounce drink from Monster, there's 240 milligrams of caffeine. In a 16-ounce cup of coffee from Starbucks, there's 330 milligrams of caffeine.

The Huffington Post reports that this past summer, the New York state attorney general's office subpoenaed Monster as part of an investigation into how energy drinks are made and marketed. Subpoenas were also sent to Living Essentials, which makes 5-Hour Energy shots, and PepsiCo, which makes AMP.