DULUTH — A Michigan woman has pleaded guilty to murder in the fatal stabbing of a Duluth woman, but says she wouldn’t have done it if she wasn’t under the influence of synthetic drugs.

Nicole Leone Revello, 29, of Marquette, Mich., entered her guilty plea Friday in Duluth. She agreed to a sentence of about 30 years, and will be formally sentenced in September.

Revello admitted she stabbed 46-year-old Lisa Kay Davis on June 2. Revello’s attorney, Brent Olson, says his client is sorry and wanted to take responsibility for what she did. Olson says Revello is a different person when she is not under the influence of synthetic drugs.

Prosecutors say Revello intentionally stabbed Davis in the back after the two argued earlier that day.