Denise Keesee, 39, pleaded guilty Monday to sexually abusing a 16-year-old boy who was a student at Sherwood High School, where she was a teacher.

Facing six counts of second-degree sexual abuse involving two students, Keesee took a plea deal and admitted to two of the counts involving one victim.

Keesee's relationship with the victim was first investigated in 2008, when the boy's mother reported finding inappropriate text messages between the teacher and her son. But the investigation was dropped until allegations involving another student surfaced in 2012.

The Washington County Sheriff's Office handled the investigation because Keesee is married to a Sherwood police officer, who was the school resource officer from 2011 to late 2012.

Deputy District Attorney Paul Maloney said Monday that Keesee told detectives she did have sex with the student in 2008. According to court records, Keesee said they had sex several times at various locations, including her home, the boy's home and a Tualatin park. The student was 16 at the time, records say.

Detective Robert Rookhuyzen said last year the relationship was long-term, and that the victim became convinced that Keesee would marry him after he graduated.

Keesee contacted Sherwood police in May 2008, according to court records, because she was worried about the student's mental health. She had received an email from the boy that contained a poem expressing regrets and suicidal thoughts, including the lines:

"im sick of life and how im lying

im sick of this earth and what im trying to do

im sick of everything just want to be true"

Rookhuyzen said it wasn't clear whether the relationship between Keesee and the student had been sexual before that email.

During the investigation, Keesee also admitted to having sexual contact with another student in 2012. According to court records, Keesee told detectives she kissed him several times in 2012 when they were alone in her classroom. She also reportedly admitted to sending him photos of herself, including one of her naked. Investigators determined that the student was 18, so no criminal charges were filed.

The charges filed against Keesee last year included allegations involving another underage student. Maloney said Monday that Keesee did not make a statement to investigators regarding her contact with him.

That former student has filed a $5.1 million lawsuit against Keesee and the Sherwood School District, alleging that she sexually abused him, her husband intimidated and harassed him and that the school failed to report the abuse.

Keesee was placed on leave in November 2012, when the latest criminal investigation began, and her husband was reassigned from his position as school resource officer. She reportedly was hired by the school as a math and special education teacher in 2006 and resigned in May.

Her husband, Adam Keesee, was placed on leave after the lawsuit against his wife was filed in June. Oregon State Police launched their own investigation of him.

Presiding Judge Kirsten Thompson, who accepted Denise Keesee’s guilty plea Monday, indicated the state would recommend a sentence of five years of probation with a number of conditions. A sentencing hearing was set for April to allow time for a pre-sentencing investigation.

Denise Keesee will remain out of custody pending the April 21 hearing.

-- Emily E. Smith