Are assaults against police on the rise?

all sources must be scholarly journals, ones that i can access for free through ebsco host or i need the sources scanned and sent to me.this paper is for a research study class.its a comprehesive literature review of 5-6 sources presentedin an integrative and critical fashion. i do belive assaults against police are on the rise. i need the theory, the hypothesis and a null hypothesis, and a research design. the research doesnt need to be carried out. my hypothesis is that assaults are on the rise. i will be graded on: discussion of studiescontains all relevant details, Synthesis:synthesis of research is coherent,consice and logical.Theoretical framework:a theoretical framework is established based on the literature discussed and sufficent evidence for the theoretical framework is provided. variables and non variables must be defined. the research plan im leaning towards is a qulatative design. so form a research plan around that (surveys,interviews etc) and what types of questions would be asked in them and who i would ask. it also needs a purpose statement